EP4134705B1 - A mobile device, a system, and a method for handling objects provided with radio frequency identifiers - Google Patents

A mobile device, a system, and a method for handling objects provided with radio frequency identifiers Download PDF

Info

Publication number
EP4134705B1
EP4134705B1 EP22177349.2A EP22177349A EP4134705B1 EP 4134705 B1 EP4134705 B1 EP 4134705B1 EP 22177349 A EP22177349 A EP 22177349A EP 4134705 B1 EP4134705 B1 EP 4134705B1
Authority
EP
European Patent Office
Prior art keywords
radio frequency
mobile device
objects
frequency identifiers
specific radio
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
EP22177349.2A
Other languages
German (de)
French (fr)
Other versions
EP4134705C0 (en
EP4134705A1 (en
Inventor
Henrik Nyman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Turck Vilant Systems Oy
Original Assignee
Turck Vilant Systems Oy
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Turck Vilant Systems Oy filed Critical Turck Vilant Systems Oy
Publication of EP4134705A1 publication Critical patent/EP4134705A1/en
Application granted granted Critical
Publication of EP4134705C0 publication Critical patent/EP4134705C0/en
Publication of EP4134705B1 publication Critical patent/EP4134705B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/0755—Position control; Position detectors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/07504—Accessories, e.g. for towing, charging, locking
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/87—Combinations of radar systems, e.g. primary radar and secondary radar
    • G01S13/878—Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P3/00—Measuring linear or angular speed; Measuring differences of linear or angular speeds
    • G01P3/42—Devices characterised by the use of electric or magnetic means
    • G01P3/50—Devices characterised by the use of electric or magnetic means for measuring linear speed
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50—Systems of measurement based on relative movement of target
    • G01S13/52—Discriminating between fixed and moving objects or between objects moving at different speeds
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50—Systems of measurement based on relative movement of target
    • G01S13/58—Velocity or trajectory determination systems; Sense-of-movement determination systems
    • G01S13/60—Velocity or trajectory determination systems; Sense-of-movement determination systems wherein the transmitter and receiver are mounted on the moving object, e.g. for determining ground speed, drift angle, ground track
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/74—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
    • G01S13/76—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted
    • G01S13/78—Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems wherein pulse-type signals are transmitted discriminating between different kinds of targets, e.g. IFF-radar, i.e. identification of friend or foe
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/87—Combinations of radar systems, e.g. primary radar and secondary radar
    • G01S13/876—Combination of several spaced transponders or reflectors of known location for determining the position of a receiver
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
    • G01S7/415—Identification of targets based on measurements of movement associated with the target
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
    • G06K7/10019—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers.
    • G06K7/10079—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
    • G06K7/10089—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions the interrogation device using at least one directional antenna or directional interrogation field to resolve the collision
    • G06K7/10099—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions the interrogation device using at least one directional antenna or directional interrogation field to resolve the collision the directional field being used for pinpointing the location of the record carrier, e.g. for finding or locating an RFID tag amongst a plurality of RFID tags, each RFID tag being associated with an object, e.g. for physically locating the RFID tagged object in a warehouse
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
    • G06K7/10366—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications
    • G06K7/10376—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications the interrogation device being adapted for being moveable
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
    • G06K7/10366—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications
    • G06K7/10376—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications the interrogation device being adapted for being moveable
    • G06K7/10405—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications the interrogation device being adapted for being moveable the interrogation device including an arrangement for sensing environmental parameters, such as a temperature or acceleration sensor, e.g. used as an on/off trigger or as a warning means
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10009—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
    • G06K7/10366—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications
    • G06K7/10415—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves the interrogation device being adapted for miscellaneous applications the interrogation device being fixed in its position, such as an access control device for reading wireless access cards, or a wireless ATM
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q10/00—Administration; Management
    • G06Q10/08—Logistics, e.g. warehousing, loading or distribution; Inventory or stock management
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
    • H04B5/70—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes
    • H04B5/77—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes for interrogation

Definitions

  • the disclosure relates to a mobile device for handling objects each being provided with an object-specific radio frequency identifier "RFID".
  • RFID object-specific radio frequency identifier
  • the mobile device can be, for example but not necessarily, a forklift.
  • the disclosure relates to a system and a method for handling objects each being provided with an object-specific radio frequency identifier.
  • the disclosure relates to a computer program for handling objects each being provided with an object-specific radio frequency identifier.
  • RFID radio frequency identifiers
  • the above-mentioned task can be however challenging because RFID-readers may read RFIDs relating to objects which are in the operating environment of a forklift or another mobile device, but which do not belong to the load of the forklift or other mobile device. Extraneous RFID reads like these may disturb the traceability of the objects and/or cause other difficulties in the management of the objects.
  • Publication US20090207024 describes a system for detecting whether an object provided with a RFID is a part of a load of a forklift or another mobile device.
  • the system utilizes spatial identification technology to define a space in front of a forklift as a load space, where the load space may be either a certain volume or area in front of the forklift. Objects within that volume or area in front of the forklift are considered on the load, while objects outside of that area are considered not on the load.
  • the spatial identification technology requires, however, careful tuning of power limits and/or other factors to achieve a situation where objects belonging to the load space are identified in a sufficiently reliable way.
  • There are also other known methods but many of them have their own limitations. For example, some known methods require that a RFID-signal is modulated in a certain way, e.g. there may be a requirement that a RFID-signal comprises in-phase "I" and quadrature "Q" components.
  • Publication US9047522 describes a radio frequency identifier "RFID" system for detecting whether an RFID tag is part of the load of a forklift.
  • RFID radio frequency identifier
  • the RFID reader system obtains tag readings and derives tag vector motion information which can be compared to the known motion of the load to distinguish tags that are part of the load from false positives which are unavoidably also within the field of the RFID reader system.
  • a forklift RFID antenna system may also make readings from load pickup to load deposit and utilize the computed tag vector motion information to distinguish tags that are part of the load from false positives.
  • the tag vector motion information my relate to tag velocity, tag acceleration, and/or rate of change of tag acceleration.
  • the two components of the RFID system may communicate information on identified tags, and/or interact, e.g. by silencing tags, so as to cooperate in identifying true positive tags in the load.
  • a portal or reader system location along the path of the forklift can be activated prior to arrival of the load to eliminate certain false positives from requiring evaluation while the forklift load is moving through the field region of such reader system.
  • Vertical motion of the load can be utilized as a way of discriminating between true positive tags in the load and false positives.
  • the two components of the RFID system i.e. the RFID reader system in the operational environment of the forklift as well as the RFID reader system in the forklift.
  • RFID radio frequency identifier
  • the mobile device can be, for example but not necessarily, a forklift.
  • a mobile device according to the invention comprises:
  • the determination whether an object belongs to the load is based on the radiation received from the object-specific RFIDs and from the fixed RFIDs, there is no need to estimate e.g. the location of the object and/or the distance between the mobile device and the object. Thus, there is no need for tuning e.g. power limits and/or other similar factors related to RFID reads. Furthermore, the above-described approach is applicable with differently modulated RFID-signals. Thus, there is no requirement that a RFID-signal should be modulated in a certain way, e.g. so that it comprises in-phase and quadrature components.
  • a system according to the invention comprises:
  • a method for handling objects each being provided with an object-specific radio frequency identifier comprises:
  • a new computer program for classifying objects based on radiation received at a mobile device from object-specific radio frequency identifiers attached to the objects and on radiation received at the mobile device from fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device.
  • a computer program according to the invention comprises computer executable instructions for controlling a programmable processor to:
  • the computer program product comprises a non-volatile computer readable medium, e.g. a compact disc "CD”, encoded with a computer program according to the invention.
  • a non-volatile computer readable medium e.g. a compact disc "CD”
  • FIGs 1a and 1b illustrate a system for handling objects.
  • the system comprises a mobile device 100 according to an exemplifying and non-limiting embodiment for handling the objects.
  • the mobile device 100 is a forklift.
  • the objects are provided with object-specific radio frequency identifiers "RFID”.
  • RFID radio frequency identifiers
  • the objects 110, 111, and 112 are provided with radio frequency identifiers "RFID" 105, 106, and 107, respectively.
  • the system comprises fixed radio frequency identifiers "RFID” attached to one or more fixed structures located in an operating environment of the mobile device 100.
  • fixed radio frequency identifiers are attached to a floor of a room in which the mobile device 100 operates.
  • two of the fixed radio frequency identifiers are denoted with references 108 and 109.
  • the fixed radio frequency identifiers are arranged to form two rows 113 and 114 so that the fixed radio frequency identifier 108 belongs to the row 113 and the fixed radio frequency identifier 109 belongs to the row 114.
  • the mobile device 100 comprises a radio frequency identifier reader "RFID-reader" 101 that comprises a radio receiver 104 for receiving radiation emitted by the object-specific RFIDs 105-107 and radiation emitted by the fixed RFIDs 108 and 109.
  • RFIDs can be either a passive RFID, an active RFID, or a battery-assisted passive RFID.
  • An active RFID has an on-board battery and periodically transmits radiation encoded with identification data.
  • the RFID-reader 101 does not necessarily comprise a radio transmitter.
  • a battery-assisted passive RFID has a battery on board and is activated when it receives radio energy transmitted by a RFID-reader.
  • a passive RFID is cheaper and smaller than an active RFID and a battery-assisted passive RFID because a passive RFID has no battery. Instead, a passive RFID uses the radio energy transmitted by a RFID-reader.
  • the RFID-reader 101 comprises a radio transmitter 103 for emitting radiation to excite the RFIDs 105-109 to emit radiation.
  • Each of the object-specific RFIDs 105-107 can be a tag attached to the corresponding object to be identified.
  • each of the fixed RFIDs 108 and 109 can be a tag attached to the floor or another fixed structure.
  • the mobile device 100 further comprises a processing system 102 that is configured to compute a speed estimate v for the mobile device 100 based on a known distance between first and second ones of the fixed RFIDs and a time-difference between receptions of radiation from the first and second ones of the fixed RFIDs.
  • the first ones of the fixed RFIDs are the RFIDs forming the row 113 and the second ones of the fixed RFIDs are the RFIDs forming the row 114.
  • the fixed RFID 108 belongs to the first ones of the fixed RFIDs and the fixed RFID 109 belongs to the second ones of the fixed RFIDs.
  • the distance between first and second ones of the fixed RFIDs is denoted with s.
  • the time-difference can be defined for example as a time-difference between maximum amplitudes of the radiations received from the first and second ones of the fixed RFIDs, or in some other suitable way.
  • the invention is however not limited to any specific ways to define the time difference.
  • the processing system 102 is configured to determine, based on radiation received from each of the object-specific RFIDs 105-107, a movement indicator indicative of movement of the mobile device 100 with respect to the object provided with the object-specific RFID under consideration.
  • the processing system 102 is configured to determine a rate of change of a phase angle d ⁇ /dt of the radiation received from each of the object-specific RFIDs.
  • the rate of change of the phase angle d ⁇ /dt represents the movement indicator related to the object-specific RFID under consideration.
  • the rate of change of the phase angle can be measured e.g. during the time interval t 1 ...
  • the processing system 102 is configured to determine a rate of change of a signal strength of the radiation received from each of the object-specific RFIDs.
  • the rate of change of the signal strength represents the movement indicator related to the object-specific RFID under consideration.
  • the rate of change of the signal strength can be measured e.g. during the time interval t 1 ... t 2 so that dRSSI / dt ⁇ RSSI t 2 ⁇ RSSI t 1 / t 2 ⁇ t 1 , where RSSI is an indicator of the signal strength of the radiation received from the object-specific RFID under consideration. It also possible to use the change RSSI(t 2 ) - RSSI(t 1 ) as the movement indicator instead of the rate of change.
  • the processing system 102 is configured to determine a Doppler-shift of the radiation received from each of the object-specific RFIDs.
  • the Doppler-shift represents the movement indicator related to the object-specific RFID under consideration.
  • the processing system 102 is configured determine two or more of the following: i) the rate of change of the phase angle d ⁇ /dt, ii) the rate of change of the received signal strength dRSSI/dt, and iii) the Doppler-shift of the received radiation, and to form each movement indicator based on these two or more determined quantities, e.g. as a weighted sum of the determined quantities.
  • the processing system 102 is configured to classify a first one or ones of the objects to be an object or objects belonging to a load of the mobile device 100 and a second one or ones of the objects to be an object or objects non-belonging to the load of the mobile device 100 in response to a situation in which
  • the object 105 is classified to be an object that belongs to the load of the mobile device 100 and the objects 106 and 107 are classified to be objects that do not belongs to the load of the mobile device 100.
  • the RFID-reader 101 and the processing system 102 are presented in figure 1a as functional entities, and thus their presentation in figure 1a does not represent any limitations concerning their physical implementation.
  • the RFID-reader 101 and the processing system 102 can be implemented with a same physical device or with separate physical devices.
  • the processing system 102 can be implemented for example with one or more processor circuits, each of which can be a programmable processor circuit provided with appropriate software, a dedicated hardware processor such as for example an application specific integrated circuit "ASIC", or a configurable hardware processor such as for example a field programmable gate array "FPGA”.
  • the processing system 102 may further comprise memory implemented for example with one or more memory circuits each of which can be e.g. a random-access memory "RAM" device.
  • FIG. 2 illustrates a schematic layout of a system according to an exemplifying and non-limiting embodiment for handling objects.
  • the fixed radio frequency identifiers "RFID” are attached to a floor or a ground on which one or more mobile devices for moving the objects, e.g. one or more forklifts, is/are configured to operate.
  • the floor or ground is divided into areas 221, 222, 223, 224, and 225.
  • Two or three boundaries of each of the areas are provided with two rows of fixed radio frequency identifiers "RFID”.
  • two of the rows of the fixed RFIDs are denoted with references 213 and 214.
  • a distance between adjacent rows is denoted with s.
  • paths of a mobile device, e.g. a forklift, for moving objects to and from the areas 221-225 are depicted with two-headed dashed line arrows.
  • Figure 3 shows a flowchart of a method according to an exemplifying and non-limiting embodiment for handling objects each being provided with an object-specific radio frequency identifier.
  • the method comprises the following actions:
  • a method comprises determining a rate of change of a phase angle of the radiation received from each of the object-specific radio frequency identifiers, where the rate of change of the phase angle is at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  • a method comprises determining a rate of change of a signal strength of the radiation received from each of the object-specific radio frequency identifiers, where the rate of change of the signal strength is at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  • a method comprises determining a Doppler-shift of the radiation received from each of the object-specific radio frequency identifiers, where the Doppler-shift is at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  • a method comprises emitting radiation from the mobile device to excite the object-specific radio frequency identifiers and the fixed radio frequency identifiers to emit radiation.
  • the mobile device is a forklift.
  • a computer program according to an exemplifying and non-limiting embodiment comprises computer executable instructions for controlling a programmable processor to carry out actions related to a method according to any of the above-described exemplifying embodiments.
  • the software modules comprise computer executable instructions for controlling a programmable processor to:
  • the above-mentioned software modules can be e.g. subroutines or functions implemented with a suitable programming language.
  • a computer readable medium e.g. a compact disc "CD”
  • a signal according to an exemplifying and non-limiting embodiment is encoded to carry information defining a computer program according to an exemplifying embodiment.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Remote Sensing (AREA)
  • Radar, Positioning & Navigation (AREA)
  • General Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Theoretical Computer Science (AREA)
  • Electromagnetism (AREA)
  • Artificial Intelligence (AREA)
  • General Health & Medical Sciences (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Structural Engineering (AREA)
  • Transportation (AREA)
  • Business, Economics & Management (AREA)
  • Mechanical Engineering (AREA)
  • Geology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Civil Engineering (AREA)
  • Economics (AREA)
  • Signal Processing (AREA)
  • Quality & Reliability (AREA)
  • Tourism & Hospitality (AREA)
  • General Business, Economics & Management (AREA)
  • Strategic Management (AREA)
  • Operations Research (AREA)
  • Marketing (AREA)
  • Human Resources & Organizations (AREA)
  • Entrepreneurship & Innovation (AREA)
  • Development Economics (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Forklifts And Lifting Vehicles (AREA)

Description

    Field of the disclosure
  • The disclosure relates to a mobile device for handling objects each being provided with an object-specific radio frequency identifier "RFID". The mobile device can be, for example but not necessarily, a forklift. Furthermore, the disclosure relates to a system and a method for handling objects each being provided with an object-specific radio frequency identifier. Furthermore, the disclosure relates to a computer program for handling objects each being provided with an object-specific radio frequency identifier.
    • Background
  • In many cases, it is important that a management system can determine which objects provided with radio frequency identifiers "RFID" belong to a load of a forklift or another mobile device for handling the objects. Under certain conditions, the above-mentioned task can be however challenging because RFID-readers may read RFIDs relating to objects which are in the operating environment of a forklift or another mobile device, but which do not belong to the load of the forklift or other mobile device. Extraneous RFID reads like these may disturb the traceability of the objects and/or cause other difficulties in the management of the objects.
  • Publication US20090207024 describes a system for detecting whether an object provided with a RFID is a part of a load of a forklift or another mobile device. The system utilizes spatial identification technology to define a space in front of a forklift as a load space, where the load space may be either a certain volume or area in front of the forklift. Objects within that volume or area in front of the forklift are considered on the load, while objects outside of that area are considered not on the load. The spatial identification technology requires, however, careful tuning of power limits and/or other factors to achieve a situation where objects belonging to the load space are identified in a sufficiently reliable way. There are also other known methods but many of them have their own limitations. For example, some known methods require that a RFID-signal is modulated in a certain way, e.g. there may be a requirement that a RFID-signal comprises in-phase "I" and quadrature "Q" components.
  • Publication US9047522 describes a radio frequency identifier "RFID" system for detecting whether an RFID tag is part of the load of a forklift. When the load is in motion relative to an RFID reader system, the RFID reader system obtains tag readings and derives tag vector motion information which can be compared to the known motion of the load to distinguish tags that are part of the load from false positives which are unavoidably also within the field of the RFID reader system. A forklift RFID antenna system may also make readings from load pickup to load deposit and utilize the computed tag vector motion information to distinguish tags that are part of the load from false positives. The tag vector motion information my relate to tag velocity, tag acceleration, and/or rate of change of tag acceleration. The two components of the RFID system may communicate information on identified tags, and/or interact, e.g. by silencing tags, so as to cooperate in identifying true positive tags in the load. A portal or reader system location along the path of the forklift can be activated prior to arrival of the load to eliminate certain false positives from requiring evaluation while the forklift load is moving through the field region of such reader system. Vertical motion of the load can be utilized as a way of discriminating between true positive tags in the load and false positives. In the system described in US9047522 there is a need for the two components of the RFID system, i.e. the RFID reader system in the operational environment of the forklift as well as the RFID reader system in the forklift.
  • Therefore, there is still a need for technical solutions for determining which objects provided with radio frequency identifiers belong to a load of a forklift or another mobile device for handling the objects.
    • Summary
  • The following presents a simplified summary in order to provide a basic understanding of some embodiments of the invention. The summary is not an extensive overview of the invention. It is neither intended to identify key or critical elements of the invention nor to delineate the scope of the invention. The following summary merely presents some concepts of the invention in a simplified form as a prelude to a more detailed description of exemplifying embodiments of the invention.
  • In accordance with the invention, there is provided a new mobile device for handling objects each being provided with an object-specific radio frequency identifier "RFID". The mobile device can be, for example but not necessarily, a forklift. A mobile device according to the invention comprises:
    • a radio frequency identifier reader configured to receive radiation emitted by the object-specific radio frequency identifiers and radiation emitted by fixed radio frequency identifiers attached to one or more fixed structures, e.g. a floor and/or walls and/or a ceiling, located in an operating environment of the mobile device, and
    • a processing system configured to:
      • compute a speed estimate for the mobile device based on a distance between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
      • determine, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
      • classify a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  • As the determination whether an object belongs to the load is based on the radiation received from the object-specific RFIDs and from the fixed RFIDs, there is no need to estimate e.g. the location of the object and/or the distance between the mobile device and the object. Thus, there is no need for tuning e.g. power limits and/or other similar factors related to RFID reads. Furthermore, the above-described approach is applicable with differently modulated RFID-signals. Thus, there is no requirement that a RFID-signal should be modulated in a certain way, e.g. so that it comprises in-phase and quadrature components.
  • In accordance with the invention, there is also provided a new system for handling objects each being provided with an object-specific radio frequency identifier. A system according to the invention comprises:
    • at least one mobile device according to invention for handling the objects,
      and
    • fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device.
  • In accordance with the invention, there is also provided a new method for handling objects each being provided with an object-specific radio frequency identifier. A method according to the invention comprises:
    • receiving, at a mobile device for moving the objects, radiation emitted by the object-specific radio frequency identifiers and radiation emitted by fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device,
    • computing a speed estimate for the mobile device based on a distance between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    • determining, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    • classifying a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  • In accordance with the invention, there is also provided a new computer program for classifying objects based on radiation received at a mobile device from object-specific radio frequency identifiers attached to the objects and on radiation received at the mobile device from fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device.
  • A computer program according to the invention comprises computer executable instructions for controlling a programmable processor to:
    • compute a speed estimate for the mobile device based on a distance between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    • determine, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    • classify a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  • In accordance with the invention, there is provided also a new computer program product. The computer program product comprises a non-volatile computer readable medium, e.g. a compact disc "CD", encoded with a computer program according to the invention.
  • Exemplifying and non-limiting embodiments are described in accompanied dependent claims.
  • Various exemplifying and non-limiting embodiments both as to constructions and to methods of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific exemplifying and non-limiting embodiments when read in conjunction with the accompanying drawings.
  • The verbs "to comprise" and "to include" are used in this document as open limitations that neither exclude nor require the existence of un-recited features.
  • The features recited in dependent claims are mutually freely combinable unless otherwise explicitly stated.
  • Furthermore, it is to be understood that the use of "a" or "an", i.e. a singular form, throughout this document does not exclude a plurality.
    • Brief description of figures
  • Exemplifying and non-limiting embodiments and their advantages are explained in greater detail below in the sense of examples and with reference to the accompanying drawings, in which:
    • figures 1a and 1b illustrate a system for handling objects, the system comprising a mobile device according to an exemplifying and non-limiting embodiment for handling the objects.
    • figure 2 illustrates a schematic layout of a system according to an exemplifying and non-limiting embodiment for handling objects, and
    • figure 3 shows a flowchart of a method according to an exemplifying and non-limiting embodiment for handling objects.
    Description of exemplifying and non-limiting embodiments
  • The specific examples provided in the description below should not be construed as limiting the scope and/or the applicability of the accompanied claims. Lists and groups of examples provided in the description are not exhaustive unless otherwise explicitly stated.
  • Figures 1a and 1b illustrate a system for handling objects. In figures 1a and 1b, three of the objects are denoted with references 110, 111, and 112. The system comprises a mobile device 100 according to an exemplifying and non-limiting embodiment for handling the objects. In this exemplifying case, the mobile device 100 is a forklift. The objects are provided with object-specific radio frequency identifiers "RFID". As illustrated in figure 1a, the objects 110, 111, and 112 are provided with radio frequency identifiers "RFID" 105, 106, and 107, respectively. The system comprises fixed radio frequency identifiers "RFID" attached to one or more fixed structures located in an operating environment of the mobile device 100. In this exemplifying case, fixed radio frequency identifiers are attached to a floor of a room in which the mobile device 100 operates. In figures 1a and 1b, two of the fixed radio frequency identifiers are denoted with references 108 and 109. As shown in figure 1b, the fixed radio frequency identifiers are arranged to form two rows 113 and 114 so that the fixed radio frequency identifier 108 belongs to the row 113 and the fixed radio frequency identifier 109 belongs to the row 114.
  • The mobile device 100 comprises a radio frequency identifier reader "RFID-reader" 101 that comprises a radio receiver 104 for receiving radiation emitted by the object-specific RFIDs 105-107 and radiation emitted by the fixed RFIDs 108 and 109. Each of the RFIDs can be either a passive RFID, an active RFID, or a battery-assisted passive RFID. An active RFID has an on-board battery and periodically transmits radiation encoded with identification data. In exemplifying cases where each of the RFIDs 105-109 is an active RFID, the RFID-reader 101 does not necessarily comprise a radio transmitter. A battery-assisted passive RFID has a battery on board and is activated when it receives radio energy transmitted by a RFID-reader.
  • A passive RFID is cheaper and smaller than an active RFID and a battery-assisted passive RFID because a passive RFID has no battery. Instead, a passive RFID uses the radio energy transmitted by a RFID-reader. In exemplifying cases where each of the RFIDs 105-109 is a passive RFID or a battery-assisted passive RFID, the RFID-reader 101 comprises a radio transmitter 103 for emitting radiation to excite the RFIDs 105-109 to emit radiation. Each of the object-specific RFIDs 105-107 can be a tag attached to the corresponding object to be identified. Correspondingly, each of the fixed RFIDs 108 and 109 can be a tag attached to the floor or another fixed structure.
  • The mobile device 100 further comprises a processing system 102 that is configured to compute a speed estimate v for the mobile device 100 based on a known distance between first and second ones of the fixed RFIDs and a time-difference between receptions of radiation from the first and second ones of the fixed RFIDs. In the exemplifying situation shown in figures 1a and 1b, the first ones of the fixed RFIDs are the RFIDs forming the row 113 and the second ones of the fixed RFIDs are the RFIDs forming the row 114. Thus, the fixed RFID 108 belongs to the first ones of the fixed RFIDs and the fixed RFID 109 belongs to the second ones of the fixed RFIDs. In figures 1a and 1b, the distance between first and second ones of the fixed RFIDs is denoted with s. The speed estimate v can be computed according to the following formula: v = s / t 2 − t 1 ,
    Figure imgb0001
     where t2 - t1 is the time-difference between receptions of radiation from the first and second ones of the fixed RFIDs. The time-difference can be defined for example as a time-difference between maximum amplitudes of the radiations received from the first and second ones of the fixed RFIDs, or in some other suitable way. The invention is however not limited to any specific ways to define the time difference.
  • The processing system 102 is configured to determine, based on radiation received from each of the object-specific RFIDs 105-107, a movement indicator indicative of movement of the mobile device 100 with respect to the object provided with the object-specific RFID under consideration. In a mobile device according to an exemplifying and non-limiting embodiment, the processing system 102 is configured to determine a rate of change of a phase angle dϕ/dt of the radiation received from each of the object-specific RFIDs. In this exemplifying embodiment, the rate of change of the phase angle dϕ/dt represents the movement indicator related to the object-specific RFID under consideration. The rate of change of the phase angle can be measured e.g. during the time interval t1... t2 so that d φ / dt ≈ φ t 2 − φ t 1 / t 2 − t 1 ,
    Figure imgb0002
     where ϕ is the phase angle of the radiation received from the object-specific RFID under consideration. It also possible to use the change ϕ(t2) - ϕ(t1) as the movement indicator instead of the rate of change.
  • In a mobile device according to an exemplifying and non-limiting embodiment, the processing system 102 is configured to determine a rate of change of a signal strength of the radiation received from each of the object-specific RFIDs. In this exemplifying embodiment, the rate of change of the signal strength represents the movement indicator related to the object-specific RFID under consideration. The rate of change of the signal strength can be measured e.g. during the time interval t1... t2 so that dRSSI / dt ≈ RSSI t 2 − RSSI t 1 / t 2 − t 1 ,
    Figure imgb0003
     where RSSI is an indicator of the signal strength of the radiation received from the object-specific RFID under consideration. It also possible to use the change RSSI(t2) - RSSI(t1) as the movement indicator instead of the rate of change.
  • In a mobile device according to an exemplifying and non-limiting embodiment, the processing system 102 is configured to determine a Doppler-shift of the radiation received from each of the object-specific RFIDs. In this exemplifying embodiment, the Doppler-shift represents the movement indicator related to the object-specific RFID under consideration.
  • In a mobile device according to an exemplifying and non-limiting embodiment, the processing system 102 is configured determine two or more of the following: i) the rate of change of the phase angle dϕ/dt, ii) the rate of change of the received signal strength dRSSI/dt, and iii) the Doppler-shift of the received radiation, and to form each movement indicator based on these two or more determined quantities, e.g. as a weighted sum of the determined quantities.
  • The processing system 102 is configured to classify a first one or ones of the objects to be an object or objects belonging to a load of the mobile device 100 and a second one or ones of the objects to be an object or objects non-belonging to the load of the mobile device 100 in response to a situation in which
    1. i) the computed speed estimate v exceeds a threshold vth, and
    2. ii) the movement indicator related to the second one or ones of the objects is indicative of a greater movement speed than the movement indicator related to the first one or ones of the objects.
  • In the exemplifying situation shown in figures 1a and 1b, the object 105 is classified to be an object that belongs to the load of the mobile device 100 and the objects 106 and 107 are classified to be objects that do not belongs to the load of the mobile device 100.
  • It is worth noting that the RFID-reader 101 and the processing system 102 are presented in figure 1a as functional entities, and thus their presentation in figure 1a does not represent any limitations concerning their physical implementation. For example, the RFID-reader 101 and the processing system 102 can be implemented with a same physical device or with separate physical devices. For example, the processing system 102 can be implemented for example with one or more processor circuits, each of which can be a programmable processor circuit provided with appropriate software, a dedicated hardware processor such as for example an application specific integrated circuit "ASIC", or a configurable hardware processor such as for example a field programmable gate array "FPGA". The processing system 102 may further comprise memory implemented for example with one or more memory circuits each of which can be e.g. a random-access memory "RAM" device.
  • Figure 2 illustrates a schematic layout of a system according to an exemplifying and non-limiting embodiment for handling objects. In this exemplifying case, the fixed radio frequency identifiers "RFID" are attached to a floor or a ground on which one or more mobile devices for moving the objects, e.g. one or more forklifts, is/are configured to operate. The floor or ground is divided into areas 221, 222, 223, 224, and 225. Two or three boundaries of each of the areas are provided with two rows of fixed radio frequency identifiers "RFID". In figure 2, two of the rows of the fixed RFIDs are denoted with references 213 and 214. A distance between adjacent rows is denoted with s. In figure 2, paths of a mobile device, e.g. a forklift, for moving objects to and from the areas 221-225 are depicted with two-headed dashed line arrows.
  • Figure 3 shows a flowchart of a method according to an exemplifying and non-limiting embodiment for handling objects each being provided with an object-specific radio frequency identifier. The method comprises the following actions:
    • action 301: receiving, at a mobile device for moving the objects, radiation emitted by the object-specific radio frequency identifiers and radiation emitted by fixed radio frequency identifiers attached to one or more fixed structures, e.g. a floor, located in an operating environment of the mobile device,
    • action 302: computing a speed estimate v for the mobile device based on a distance s between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    • action 303: determining, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    • action 304: classifying a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  • A method according to an exemplifying and non-limiting embodiment comprises determining a rate of change of a phase angle of the radiation received from each of the object-specific radio frequency identifiers, where the rate of change of the phase angle is at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  • A method according to an exemplifying and non-limiting embodiment comprises determining a rate of change of a signal strength of the radiation received from each of the object-specific radio frequency identifiers, where the rate of change of the signal strength is at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  • A method according to an exemplifying and non-limiting embodiment comprises determining a Doppler-shift of the radiation received from each of the object-specific radio frequency identifiers, where the Doppler-shift is at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  • A method according to an exemplifying and non-limiting embodiment comprises emitting radiation from the mobile device to excite the object-specific radio frequency identifiers and the fixed radio frequency identifiers to emit radiation.
  • In a method according to an exemplifying and non-limiting embodiment, the mobile device is a forklift.
  • A computer program according to an exemplifying and non-limiting embodiment comprises computer executable instructions for controlling a programmable processor to carry out actions related to a method according to any of the above-described exemplifying embodiments.
  • A computer program according to an exemplifying and non-limiting embodiment comprises software modules for classifying objects based on:
    1. i) radiation received at a mobile device from object-specific radio frequency identifiers attached to the objects, and
    2. ii) radiation received at the mobile device from fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device.
  • The software modules comprise computer executable instructions for controlling a programmable processor to:
    • compute a speed estimate for the mobile device based on a distance between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    • determine, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    • classify a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  • The above-mentioned software modules can be e.g. subroutines or functions implemented with a suitable programming language.
  • A computer program product according to an exemplifying and non-limiting embodiment comprises a computer readable medium, e.g. a compact disc "CD", encoded with a computer program according to an exemplifying embodiment.
  • A signal according to an exemplifying and non-limiting embodiment is encoded to carry information defining a computer program according to an exemplifying embodiment.
  • The specific examples provided in the description given above should not be construed as limiting the scope and/or the applicability of the appended claims. Lists and groups of examples provided in the description given above are not exhaustive unless otherwise explicitly stated.

Claims (15)

  1. A mobile device (100) for handling objects each being provided with an object-specific radio frequency identifier (105-107), the mobile device comprising a radio frequency identifier reader (101) configured to receive radiation emitted by the object-specific radio frequency identifiers and radiation emitted by fixed radio frequency identifiers (108, 109) attached to one or more fixed structures located in an operating environment of the mobile device, characterized in that the mobile device further comprises a processing system (102) configured to:
    - compute a speed estimate for the mobile device based on a distance (s) between first and second ones of the fixed radio frequency identifiers and a time-difference (t2 - t1) between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    - determine, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    - classify a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  2. A mobile device according to claim 1, wherein the processing system is configured to determine a rate of change of a phase angle of the radiation received from each of the object-specific radio frequency identifiers, the rate of change of the phase angle being at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  3. A mobile device according to claim 1 or 2, wherein the processing system is configured to determine a rate of change of a signal strength of the radiation received from each of the object-specific radio frequency identifiers, the rate of change of the signal strength being at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  4. A mobile device according to any one of claims 1-3, wherein the processing system is configured to determine a Doppler-shift of the radiation received from each of the object-specific radio frequency identifiers, the Doppler-shift being at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  5. A mobile device according to any one of claims 1-4, wherein the radio frequency identifier reader comprises a radio transmitter (103) configured to emit radiation to excite the object-specific radio frequency identifiers and the fixed radio frequency identifiers to emit radiation.
  6. A mobile device according to any of claims 1-5, wherein the mobile device is a forklift.
  7. A system for handling objects each being provided with an object-specific radio frequency identifier, the system comprising:
    - at least one mobile device (100) according to any one of claims 1-6 for handling the objects, and
    - fixed radio frequency identifiers (108, 109) attached to one or more fixed structures located in an operating environment of the mobile device.
  8. A system according to claim 7, wherein the fixed radio frequency identifiers are attached to a floor or a ground on which the mobile device is configured to operate.
  9. A system according to claim 8, wherein the floor or ground is divided into areas (221-225) and one or more boundaries of each of the areas are provided with two rows (213, 214) of the fixed radio frequency identifiers, a distance between the rows being the distance (s) between the first and second ones of the fixed radio frequency identifiers.
  10. A method for handling objects each being provided with an object-specific radio frequency identifier, the method comprising receiving (301), at a mobile device for moving the objects, radiation emitted by the object-specific radio frequency identifiers and radiation emitted by fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device, characterized in that the method comprises:
    - computing (302) a speed estimate for the mobile device based on a distance (s) between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    - determining (303), based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    - classifying (304) a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
  11. A method according to claim 10, wherein the method comprises determining a rate of change of a phase angle of the radiation received from each of the object-specific radio frequency identifiers, the rate of change of the phase angle being at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  12. A method according to claim 10 or 11, wherein the method comprises determining a rate of change of a signal strength of the radiation received from each of the object-specific radio frequency identifiers, the rate of change of the signal strength being at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  13. A method according to any one of claims 10-12, wherein the method comprises determining a Doppler-shift of the radiation received from each of the object-specific radio frequency identifiers, the Doppler-shift being at least a part of the movement indicator related to the object-specific radio frequency identifier under consideration.
  14. A method according to any one of claims 10-13, wherein the method comprises emitting radiation from the mobile device to excite the object-specific radio frequency identifiers and the fixed radio frequency identifiers to emit radiation.
  15. A computer program for classifying objects based on radiation received at a mobile device from object-specific radio frequency identifiers attached to the objects and on radiation received at the mobile device from fixed radio frequency identifiers attached to one or more fixed structures located in an operating environment of the mobile device, characterized in that the computer program comprises computer executable instructions for controlling a programmable processor to:
    - compute a speed estimate for the mobile device based on a distance between first and second ones of the fixed radio frequency identifiers and a time-difference between receptions of radiation from the first and second ones of the fixed radio frequency identifiers,
    - determine, based on radiation received from each of the object-specific radio frequency identifiers, a movement indicator indicative of movement of the mobile device with respect to the object provided with the object-specific radio frequency identifier under consideration, and
    - classify a first one of the objects to be an object belonging to a load of the mobile device and a second one of the objects to be an object non-belonging to the load of the mobile device in response to a situation in which i) the computed speed estimate exceeds a threshold and ii) the movement indicator related to the second one of the objects is indicative of a greater movement speed than the movement indicator related to the first one of the objects.
EP22177349.2A 2021-08-10 2022-06-06 A mobile device, a system, and a method for handling objects provided with radio frequency identifiers Active EP4134705B1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FI20215845A FI129809B (en) 2021-08-10 2021-08-10 Mobile device, system and method for handling objects equipped with radio frequency identifiers

Publications (3)

Publication Number Publication Date
EP4134705A1 EP4134705A1 (en) 2023-02-15
EP4134705C0 EP4134705C0 (en) 2023-07-12
EP4134705B1 true EP4134705B1 (en) 2023-07-12

Family

ID=81941023

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22177349.2A Active EP4134705B1 (en) 2021-08-10 2022-06-06 A mobile device, a system, and a method for handling objects provided with radio frequency identifiers

Country Status (4)

Country Link
US (1) US12304788B2 (en)
EP (1) EP4134705B1 (en)
CN (1) CN115906902A (en)
FI (1) FI129809B (en)

Family Cites Families (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6600418B2 (en) * 2000-12-12 2003-07-29 3M Innovative Properties Company Object tracking and management system and method using radio-frequency identification tags
US7667575B2 (en) * 2004-07-30 2010-02-23 Reva Systems Corporation Location virtualization in an RFID system
US7403120B2 (en) * 2004-09-29 2008-07-22 Symbol Technologies, Inc. Reverse infrastructure location system and method
EP1886378B1 (en) * 2005-05-13 2015-09-16 EMS Technologies, Inc. Tine-mounted antenna for an rfid system
US7567179B2 (en) * 2005-10-17 2009-07-28 Reva Systems Corporation Configuration management system and method for use in an RFID system including a multiplicity of RFID readers
US7924141B2 (en) * 2006-12-01 2011-04-12 Round Rock Research, Llc RFID communication systems and methods, and RFID readers and systems
US7973644B2 (en) * 2007-01-30 2011-07-05 Round Rock Research, Llc Systems and methods for RFID tag arbitration where RFID tags generate multiple random numbers for different arbitration sessions
KR20080103254A (en) 2007-05-23 2008-11-27 에스케이 텔레콤주식회사 Position Measuring Method of Radio Identification Reader using Beacon and Radio Identification System for It
US7619524B2 (en) 2007-07-20 2009-11-17 Symbol Technologies, Inc. Identifying RFID tag moving coherently with reader
US9047522B1 (en) * 2008-02-14 2015-06-02 Intermec Ip Corp. Utilization of motion and spatial identification in mobile RFID interrogator
US9007178B2 (en) * 2008-02-14 2015-04-14 Intermec Ip Corp. Utilization of motion and spatial identification in RFID systems
US8237563B2 (en) 2008-02-14 2012-08-07 Intermec Ip Corp. Utilization of motion and spatial identification in mobile RFID interrogator
JP2009222590A (en) * 2008-03-17 2009-10-01 Fujitsu Ltd Testing device and testing method
US20090322489A1 (en) * 2008-04-14 2009-12-31 Christopher Jones Machine vision rfid exciter triggering system
US8188863B2 (en) * 2008-11-26 2012-05-29 Symbol Technologies, Inc. Detecting loading and unloading of material
US8810399B2 (en) 2011-03-16 2014-08-19 Avery Dennison Corporation Detection of groups of RFID tags
US8731785B2 (en) * 2011-03-18 2014-05-20 The Raymond Corporation Dynamic stability control systems and methods for industrial lift trucks
US9547079B2 (en) * 2014-02-06 2017-01-17 Fedex Corporate Services, Inc. Object tracking method and system
EP2927838B1 (en) * 2014-04-02 2016-03-16 Sick Ag System and method for identifying and locating objects
US10127417B2 (en) 2016-01-08 2018-11-13 Disney Enterprises, Inc. Systems and methods for determining interaction states of wireless tags based on probability distributions
US10049244B2 (en) * 2016-05-25 2018-08-14 Symbol Technologies, Llc Motion-controlled arrangement for, and method of, locating targets with improved performance in a venue
US11068841B1 (en) 2017-06-08 2021-07-20 Amazon Technologies, Inc. RFID enabled and location aware pallet mover
JP2019109610A (en) * 2017-12-15 2019-07-04 東芝テック株式会社 Reading device and program
WO2020038568A1 (en) * 2018-08-21 2020-02-27 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Rfid reader and method for reading out rfid tags

Also Published As

Publication number Publication date
EP4134705C0 (en) 2023-07-12
EP4134705A1 (en) 2023-02-15
US20230050026A1 (en) 2023-02-16
CN115906902A (en) 2023-04-04
US12304788B2 (en) 2025-05-20
FI129809B (en) 2022-09-15
FI20215845A1 (en) 2022-09-15

Similar Documents

Publication Publication Date Title
US11915589B2 (en) Anti-collision system and method for ground vehicles
US9013282B2 (en) Object tracking apparatus and method, and sensor position designating method
US7567179B2 (en) Configuration management system and method for use in an RFID system including a multiplicity of RFID readers
US10157337B1 (en) Pre-notification with RFID dock door portals
EP2176844B1 (en) Systems and methods for object localization and path identification based on rfid sensing
US20110050421A1 (en) Systems, methods and apparatus for determining direction of motion of a radio frequency identification (rfid) tag
US20140139367A1 (en) Method for producing at least information for track fusion and association for radar target tracking, and storage medium thereof
EP3304121B1 (en) Systems and methods for locating and determining the orientation of a handheld device
EP1953565B1 (en) Secondary surveillance radar and method of analyzing replies for secondary surveillance radar
JP2010502951A (en) ID Doppler movement detector
Buffi et al. The SARFID technique for discriminating tagged items moving through a UHF-RFID gate
KR102071465B1 (en) System and method for detecting a vehicle access in mine
US20080042838A1 (en) Identification and location of RF tagged articles
US11408988B2 (en) System and method for acoustic vehicle location tracking
EP3571521B1 (en) System and method for detecting movement of a mobile asset and controlling operations of the asset based on its movement
US9881185B2 (en) Systems and methods for estimation of a population of passive RFID sensors
US9047522B1 (en) Utilization of motion and spatial identification in mobile RFID interrogator
US11003180B2 (en) Communication system and machine arrangement
US12304788B2 (en) Mobile device, a system, and a method for handling objects provided with radio frequency identifiers
Nepa et al. I-READ 4.0: Internet-of-READers for an efficient asset management in large warehouses with high stock rotation index
CN114333329A (en) Parking detection method, parking detection equipment and storage medium
CN109034313A (en) Parking stall use state detection method, system, reflective tape and anticollision strip
US7847722B2 (en) Secondary surveillance radar and method of analyzing replies for secondary surveillance radar
JP4449763B2 (en) Mobile object, information receiver, traveling direction determination device, traveling direction determination method, and traveling direction determination program
FI20237200A1 (en) A mobile device and a method for handling objects provided with radio frequency identifiers

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20221108

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: GRANT OF PATENT IS INTENDED

INTG Intention to grant announced

Effective date: 20230317

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE PATENT HAS BEEN GRANTED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

REG Reference to a national code

Ref country code: CH

Ref legal event code: EP

REG Reference to a national code

Ref country code: DE

Ref legal event code: R096

Ref document number: 602022000202

Country of ref document: DE

REG Reference to a national code

Ref country code: IE

Ref legal event code: FG4D

U01 Request for unitary effect filed

Effective date: 20230712

U07 Unitary effect registered

Designated state(s): AT BE BG DE DK EE FI FR IT LT LU LV MT NL PT SE SI

Effective date: 20230721

REG Reference to a national code

Ref country code: LT

Ref legal event code: MG9D

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231013

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231112

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: RS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

Ref country code: NO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231012

Ref country code: IS

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231112

Ref country code: HR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

Ref country code: GR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20231013

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: PL

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

REG Reference to a national code

Ref country code: DE

Ref legal event code: R097

Ref document number: 602022000202

Country of ref document: DE

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SM

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

Ref country code: RO

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

Ref country code: CZ

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

Ref country code: SK

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20240415

U20 Renewal fee for the european patent with unitary effect paid

Year of fee payment: 3

Effective date: 20240625

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: MC

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20230712

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20240606

U20 Renewal fee for the european patent with unitary effect paid

Year of fee payment: 4

Effective date: 20250627

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CY

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20220606

REG Reference to a national code

Ref country code: CH

Ref legal event code: H13

Free format text: ST27 STATUS EVENT CODE: U-0-0-H10-H13 (AS PROVIDED BY THE NATIONAL OFFICE)

Effective date: 20260127

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: HU

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT; INVALID AB INITIO

Effective date: 20220606

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20250630